501: Function

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A definition of function

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Topics

About: set

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The table of contents of this article

• Starting Context
• Target Context
• Orientation
• Main Body
• 1: Definition
• 2: Note

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Starting Context

• The reader knows a definition of relation.

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Target Context

• The reader will have a definition of function.

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Orientation

There is a list of definitions discussed so far in this site.

There is a list of propositions discussed so far in this site.

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Main Body

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1: Definition

Any relation, $F$, such that for each $⟨p_1,p_2⟩,⟨p_1,p_3⟩\in F$, $p_2=p_3$, which means that any element of the domain has the unique corresponding element in the range

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2: Note

'map' is different from 'function' in this definition in that it has the codomain, which does not necessarily equal the range, although a map is often called "function".

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References

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